SSH: Use Remote Bash / KSH source Command Set Variable Locally From a Remote Server

Posted on in Categories , , last updated December 4, 2012

I have setup a master / local server combination using OpenSSH. My local server depends upon master server for a remote sourcing. The remote sourcing should set a large number of variables locally in a bash shell script. The code is:

[email protected] $ source ssh [email protected] "/service/ --mode=slave"
echo “$var”

The var is not setting and I am getting various errors. How can I do a remote “source” of a bash script file (from and set a shell variable locally at

Unix / Linux Shell: Parse Text CVS File Separator By Field

Posted on in Categories , , last updated March 4, 2014

I work for a small ISP (Internet Service Provider) and we are using Linux and Unix-like operating system with bash shell. I want to write a shell script to parse the csv file line by line. Then line must be parse again field by field. The sample input file is as follows:,username,groupname,homedir,md5password,permission,secondarygroup

I need to extract each of these,username,groupname,homedir,md5password,permission,secondarygroup fields and passed to the different system utilities. How do I write a shell script to automate this task and use the bash shell to parse a text file?

Bash: Get The Last Argument Passed to a Shell Script

Posted on in Categories last updated June 26, 2012

I‘m writing a bash wrapper script that will pass arguments to the command. I need to find out the last argument if I call the wrapper as follows:

./wrapper -a -b –longarg=foo thisfilename.txt
./wrapper -a -b thisfilename.txt
./wrapper -a –next=true thisfilename.txt

=> $@ is all of them.
=> $0 is script name.
=> $1 is first arg.

I want thisfilename.txt stored in a shell variable called $last. How do I find the last argument passed to a shell script written in bash or ksh under Unix like operating systems?

Linux / Unix: Sed Substitute Multiple Patterns [ Find & Replace ]

Posted on in Categories last updated January 20, 2012

I‘m using the date +’%D_%T’ to store Unix system date and time in a shell variable called $_now:

_now=”$(date +’%D_%T’)”
echo $_now


I’d like to replace / and : with _. I’m aware of the following sed command:

sed ‘s/\//_/g
> s/:/_/g’ <<<"$_now"


How do I specify two pattern within the same sed command to replace | and : with _ so that I can get output as 01_20_12_16_10_42?